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Differences Between: [Versions 310 and 311] [Versions 39 and 311]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  namespace core_backup;
  18  
  19  use backup;
  20  use base_element_struct_exception;
  21  use encrypted_final_element;
  22  
  23  defined('MOODLE_INTERNAL') || die();
  24  
  25  global $CFG;
  26  require_once($CFG->dirroot . '/backup/util/includes/backup_includes.php');
  27  require_once($CFG->dirroot . '/backup/util/includes/restore_includes.php');
  28  require_once($CFG->dirroot . '/backup/moodle2/backup_custom_fields.php');
  29  
  30  /**
  31   * Tests for the handling of encrypted contents in backup and restore.
  32   *
  33   * @package core_backup
  34   * @copyright 2016 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
  35   * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36   */
  37  class backup_encrypted_content_test extends \advanced_testcase {
  38  
  39      public function setUp(): void {
  40          if (!function_exists('openssl_encrypt')) {
  41              $this->markTestSkipped('OpenSSL extension is not loaded.');
  42  
  43          } else if (!function_exists('hash_hmac')) {
  44              $this->markTestSkipped('Hash extension is not loaded.');
  45  
  46          } else if (!in_array(backup::CIPHER, openssl_get_cipher_methods())) {
  47              $this->markTestSkipped('Expected cipher not available: ' . backup::CIPHER);
  48          }
  49      }
  50  
  51      public function test_encrypted_final_element() {
  52  
  53          $this->resetAfterTest(true);
  54  
  55          // Some basic verifications.
  56          $efe = new encrypted_final_element('test', array('encrypted'));
  57          $this->assertInstanceOf('encrypted_final_element', $efe);
  58          $this->assertSame('test', $efe->get_name());
  59          $atts = $efe->get_attributes();
  60          $this->assertCount(1, $atts);
  61          $att = reset($atts);
  62          $this->assertInstanceOf('backup_attribute', $att);
  63          $this->assertSame('encrypted', $att->get_name());
  64  
  65          // Using a manually defined (incorrect length) key.
  66          $efe = new encrypted_final_element('test', array('encrypted'));
  67          $key = 'this_in_not_correct_32_byte_key';
  68          try {
  69              set_config('backup_encryptkey', base64_encode($key), 'backup');
  70              $efe->set_value('tiny_secret');
  71              $this->fail('Expecting base_element_struct_exception exception, none happened');
  72          } catch (\Exception $e) {
  73              $this->assertInstanceOf('base_element_struct_exception', $e);
  74              $this->assertEquals('encrypted_final_element incorrect key length', $e->errorcode);
  75  
  76          }
  77  
  78          // Using a manually defined (correct length) key.
  79          $efe = new encrypted_final_element('test', array('testattr', 'encrypted'));
  80          $key = hash('md5', 'Moodle rocks and this is not secure key, who cares, it is a test');
  81          set_config('backup_encryptkey', base64_encode($key), 'backup');
  82          $this->assertEmpty($efe->get_value());
  83          $secret = 'This is a secret message that nobody else will be able to read but me 💩 ';
  84          $efe->set_value($secret);
  85          $atts = $efe->get_attributes();
  86          $this->assertCount(2, $atts);
  87          $this->assertArrayHasKey('encrypted', $atts); // We added it explicitly.
  88          $this->assertTrue($atts['encrypted']->is_set());
  89          $this->assertSame('true', $atts['encrypted']->get_value());
  90          $this->assertNotEmpty($efe->get_value());
  91          $this->assertTrue($efe->is_set());
  92          // Get the crypted content and decrypt it manually.
  93          $ctext = $efe->get_value();
  94          $hmaclen = 32; // SHA256 is 32 bytes.
  95          $ivlen = openssl_cipher_iv_length(backup::CIPHER);
  96          list($hmac, $iv, $text) = array_values(unpack("a{$hmaclen}hmac/a{$ivlen}iv/a*text", base64_decode($ctext)));
  97          $this->assertSame(hash_hmac('sha256', $iv . $text, $key, true), $hmac);
  98          $this->assertSame($secret, openssl_decrypt($text, backup::CIPHER, $key, OPENSSL_RAW_DATA, $iv));
  99  
 100          // Using the default site-generated key.
 101          $efe = new encrypted_final_element('test', array('testattr'));
 102          $this->assertEmpty($efe->get_value());
 103          $secret = 'This is a secret message that nobody else will be able to read but me 💩 ';
 104          $efe->set_value($secret);
 105          $atts = $efe->get_attributes();
 106          $this->assertCount(2, $atts);
 107          $this->assertArrayHasKey('encrypted', $atts); // Was added automatcally, we did not specify it.
 108          $this->assertTrue($atts['encrypted']->is_set());
 109          $this->assertSame('true', $atts['encrypted']->get_value());
 110          $this->assertNotEmpty($efe->get_value());
 111          $this->assertTrue($efe->is_set());
 112          // Get the crypted content and decrypt it manually.
 113          $ctext = $efe->get_value();
 114          $hmaclen = 32; // SHA256 is 32 bytes.
 115          $ivlen = openssl_cipher_iv_length(backup::CIPHER);
 116          list($hmac, $iv, $text) = array_values(unpack("a{$hmaclen}hmac/a{$ivlen}iv/a*text", base64_decode($ctext)));
 117          $key = base64_decode(get_config('backup', 'backup_encryptkey'));
 118          $this->assertSame(hash_hmac('sha256', $iv . $text, $key, true), $hmac);
 119          $this->assertSame($secret, openssl_decrypt($text, backup::CIPHER, $key, OPENSSL_RAW_DATA, $iv));
 120      }
 121  }